Security

OCSP stapling

Server pre-fetches a signed revocation response and attaches it to the handshake.


In plain terms

Faster than client-side OCSP and doesn't leak browsing history to the CA.

Origin

RFC 6066 added the TLS Certificate Status Request extension in 2011. Lets the server pre-fetch a signed OCSP response and ship it during the handshake instead of the client hitting the CA directly.

Where it shows up in production
  • Nginx, Apache, Caddy All three support ssl_stapling. Removes one extra round-trip and stops the CA seeing every visitor's IP.
  • Must-Staple flag A certificate extension that requires stapling. Lets browsers fail closed when stapling is broken.
On Semicolony
Sources & further reading
Found this useful?